The principal objective of this project will be to elucidate the properties and function of the isoenzymic forms of dynein in cilia and sperm flagella. We shall prepare immune sera containing specific antibodies against each of the dynein isoenzymes from sea urchin sperm flagella, and then examine their effects upon the motility of demembranated sperm, and upon the ATPase activity of the dynein isoenzymes. The tissue and species specificity of these antibodies will be determined by examining their effect upon the motility of demembranated cilia and sperm from various animals, including mammals. By suitable fractionation of these immune sera, we shall attempt to isolate antibodies to dynein that have little species specificity. These antibodies will then be used as immunohistochemical stains to localize sites of dynein in the mitotic apparatus, cytoplasmic microtubules, and cytoplasm of various types of cells. We shall also prepare specific antisera to other protein components of the flagellar axoneme, and use them to determine the locations of these proteins in the axonemal structure and to examine their role in the mechanism of motility.